The specific aims of this investigation are to examine and quantify the relationships of hormonal factors, a variety of nutrients, and brand of cigarettes with the subsequent risk of coronary heart disease (CHD) and pulmonary embolism (PE) in a cohort of 121,964 female registered nurses aged 38 to 63 years. This cohort was established in 1976 to study risk factors for breast cancer, and follow-up questionnaires have been administered every two years subsequently. Funding was secured to identify cardiovascular risk factors from 1979-83, and the present proposal is to extend that work. Fatal cardiovascular events are documented by death certificates and confirmed and classified by review of hospital records, autopsy reports and interviews with next of kin. The mortality follow-up for the cohort is virtually 100%. Follow-up of the cohort for non-fatal cardiovascular events in 1982 is over 94% of the original 121, 964 members. Incident cases of non-fatal CHD and PE are reported on the questionnaires. Subsequent to this self-report, permission is obtained to review medical records and confirm these reports. This record review also allows for classification of these endpoints into diagnostic subtypes. We are continuing to gather data by questionnaire every two years on use of post-menopausal hormones, diet, exercise, smoking and other exposures. Incident cases of non-fatal myocardial infarction, PE and angina pectoris will also be reported on these questionnaires. Death searches for all non-respondents using the National Death Index will ensure the identification of all remaining incident fatal events. The large size of this cohort is necessary to provide adequate power to analyze the medical consequences of these cardiovascular risk factors in women. The nurses in this cohort are knowledgeable about health and have proven to be very cooperative in providing detailed and reliable information. Th large sample size, prospective design and unusually good follow-up of this established cohort, combined with the relatively low cost, makes this a valuable opportunity to study hormonal and nutritional risk factors for cardiovascular disease in women.